Nissen (1) is inaccurate in attributing any state of confusion in nutritional knowledge to Ancel Keys. Keys' famous Seven Countries Study, following an ecological design, found a strong correlation (r = 0.84) between mean intake of saturated lipids (as a percentage of total energy intake) and coronary mortality in 16 regions. These results, with the inherent limitations of an ecological design, agree with subsequent stronger evidence and with the U.S. DGAC in limiting saturated lipids (and their main sources, whole-fat dairy and red and processed meats) but not total lipids.